Definition of ex post facto in English:

ex post facto

adjective

  • Having retroactive effect or force.

    • ‘ex post facto laws’
    backdated, retroactive, ex post facto, backward-looking

Pronunciation

ex post facto

/ˌeks pōst ˈfaktō/ /ˌɛks poʊst ˈfæktoʊ/

adverb

  • Retroactively.

    • ‘the law is being applied ex post facto’

Pronunciation

ex post facto

/ˌeks pōst ˈfaktō/ /ˌɛks poʊst ˈfæktoʊ/

Origin

Erroneous division of Latin ex postfacto ‘in the light of subsequent events’.